Dear Dr Hussein

In addition to the nanofluid mentioned by Ali there is the carbon nanotubes. According to many literature it has the highest thermal conductivity.

Regards

List of Nano particles include:

1. Silicon Carbide (SiC).

2. Silicon Dioxide (SiO2).

3. Titanium Dioxide (TiO2).

4. Aluminum Oxide (Al2O3)

5. Cupric Oxide (CuO)

Thanks Ali. What do you think which one is more effective to improve the PVT efficiency?

Based on the literature review I have done it is the Silicon carbide compound. However, it is important to note that not much research have been conducted for this specific application (PVT). 

Thanks Ali for the information. As I mentioned before there are many challenging questions in this field.

Dear Dr Hussein

In addition to the nanofluid mentioned by Ali there is the carbon nanotubes. According to many literature it has the highest thermal conductivity.

Regards

Thanks Miqdam. I think thermal conductivity is highly important. However, there is some other parameters important to be consider.

Dear Dr Kazem

There many other parameter have to be considered, such as nano-material addition fraction, mixing style, suspension rate, and the system design.

Regards

Any type of nanofluid used in heat exchangers for thermal applications can be used in PV / T collector with liquid. The most used nanofluids are mentioned by Ali:

Silicon Carbide (SiC), Silicon Dioxide (SiO2), Titanium Dioxide (TiO2),  Aluminum Oxide (Al2O3), Cupric Oxide (CuO)

Thank El Amine: What about carbon? Which one has the highest thermal conductivity?

Diphenyl Oxide/Biphenyl Eutectic Mixture would be meeting your requirement

the following attachment would help you